The present disclosure relates to an ultrasonic processing apparatus and an ultrasonic processing method, and in particular, relates to an ultrasonic processing apparatus and an ultrasonic processing method by which it is possible to more clearly depict the difference in hardness in elastography.
In the elastography that evaluates the hardness of a tissue using ultrasonic waves, information of colors (hue of a HSV color system) has been mainly used to express portions which have different hardness and distributed in the tissue.
However, there is a case where it is difficult to sufficiently detect the difference by human sight in the expression using the colors if the difference in the hardness per the portion is minor.
In order to differentially depict the portions having small differences, a system of narrowing a setting of Region of Interest (ROI) to narrow a dynamic range of a viscoelastic coefficient and subdividing gradation expression by colors is used. However, in this case, it is difficult to simultaneously express the global difference in the hardness. In addition, it is typically difficult to set the portions having the small differences as ROI and the detection time for changing the setting of ROI also increases.
Technology disclosed in International Publication No. 2010/044385 or International Publication No. 2005/025425 has been proposed. International Publication No. 2010/044385 discloses that the depiction of the portions having different hardness is clarified through appropriate setting of a threshold value by calculating a histogram of the measured elasticity.
In International Publication No. 2005/025425, technology of performing the depiction of the portions through signal processing, and superimposing the result on a display image has been proposed.
However, in the technology disclosed in International Publication No. 2010/044385, the display is optimized within the given ROI, and therefore, the view is different in global distribution of the hardness and in local distribution of the hardness. In addition, the technology disclosed in International Publication No. 2005/025425 includes a process according to various threshold values or a process based on empirical results, and therefore, there is a concern that presentation of results of a recognition process of a viscoelastic coefficient itself may mislead interpretation by a human as an inspector.